1. Field of the Invention
The present invention relates to a management apparatus, management method, and program, which acquire and manage a job log in a printing system for performing mass printing in a short time.
2. Description of the Related Art
There has conventionally been a management technique of recording the history of print jobs executed in a printing system including a multifunction printer (to be referred to as an MFP hereinafter) using electrophotography.
Data stored as a job log includes the job sender, the sending time, the number of pages, and the information of attribute items such as color/monochrome. A conventional MFP uses a scheme called a ring buffer to record such a job log. The ring buffer sequentially records logs. When the recording capacity has run out, an old log is erased to store a new log. In conventional job log management, considering the period of time until the ring buffer runs out based on predetermined estimation, a management apparatus periodically accesses the MFP to acquire the log information and manages it in another storage area. This aims at uninterrupted log management.
However, this scheme can suffer an unexpected case, as a matter of course. If the MFP has processed jobs beyond the limitation before access of the management apparatus, the ring buffer capacity runs out, and some logs are erased.
Recently growing needs for security are stimulating some systems to manage the actual image of a printed content as a content log. The above-described job log containing no image data will be referred to as an attribute information log here for the sake of discrimination from the content log using an image.
To record content logs, every time the MFP prints a print job, it generates image data for a log and periodically sends accumulated image data to a management apparatus or the like as content logs. The management apparatus that stores the content logs receives the data and achieves log management. The content logs also inevitably put a squeeze on the recording capacity when the MFP has processed jobs beyond the limitation.
Some prior-art techniques cope with such a situation by, for example, outputting a warning and stopping job execution when no recording capacity remains for a content log. These techniques also reduce the data amount of a content log when the remaining recording capacity has decreased (Japanese Patent Laid-Open No. 2006-293833).
Some other techniques define the accuracy of recorded data in accordance with a keyword contained in a document (Japanese Patent Laid-Open No. 2007-079901).
The recent development of the electrophotographic technology allows implementing a printing system that causes an MFP to perform mass printing in a short time. Such a printing system is also used for light commercial printing called print on demand (to be referred to as POD hereinafter).
One of application purposes of POD is variable data print (to be referred to as VDP hereinafter) which prints an enormous number of copies of a printed product, that is, a document including a fixed portion and a variable portion contents of which change for each copy. When an MFP prints a VDP job, a print job may be generated for each copy.
In addition, a printing method called a page mode is used in the POD. When executing printing in the page mode, a job is divided into print jobs each corresponding to one page of a printed product or one paper sheet having two, obverse and reverse pages, and then submitted to the MFP.
If the above-described two techniques are simultaneously applied, jobs as much as (number of pages of target printed product)×(total number of copies) are consequently submitted to the MFP at once. For example, when printing 1,000 copies of a booklet having 100 pages, the number of jobs submitted at once is 50,000 or 100,000. That is, in the VDP or page mode, print jobs more than before are submitted to the MFP in a short time. As a result, the management apparatus handles an enormous number of job logs by force of necessity in such print modes unique to POD.
In POD, printing of a printed product generally starts upon receiving compensation based on an order from a client. In the VDP or page mode, it is difficult to determine, in an enormous number of logs, the range of printing based on a series of print requests. However, there is a strong demand for managing a log associated with a series of print requests.
In the VDP or page mode, the MFP accumulates job logs more than the previous expectation during a short period of time. Needless to say, this raises the possibility that the management apparatus misses logs because of a delay in acquisition.
Printing in the field of POD or the like is particularly productivity-oriented, and it is important to carry out requested printing as efficiently as possible. Hence, the resolution of Japanese Patent Laid-Open No. 2006-293833 which stops printing even if printing is possible cannot be employed because it reduces the production efficiency. In printing of POD, the contents of the printed product change depending on the client. It is therefore difficult for the administrator or the like to set a unified keyword to be used to identify, for example, the importance of a document, and the technique of Japanese Patent Laid-Open No. 2007-079901 cannot solve the above-described problem.
That is, the above-described conventional techniques cannot achieve flexible log management adaptive to printing in the field of POD or the like. A strong demand has arisen for enabling the management apparatus to acquire every log information before the storage area of a ring buffer or the like runs out even under such printing environments. As for content logs based on an enormous number of jobs, each log has a large size, and the recording capacity becomes short.